From 1575d97a6b12d9c2fdd5160559eae5a73a3fd44d Mon Sep 17 00:00:00 2001
From: Sears Russell <sears@cs.berkeley.edu>
Date: Thu, 5 Oct 2006 22:08:42 +0000
Subject: [PATCH] Fixed recovery bug.  TregionDealloc was being called during
 redo(), causing an assert to fail.  Without the assert, would have gone into
 infinite recursion.

---
 src/lladd/operations/regions.c | 50 +++++++++++++++++++++++++++-------
 test/lladd/check_regions.c     | 39 ++++++++++++++++++++++++++
 2 files changed, 79 insertions(+), 10 deletions(-)

diff --git a/src/lladd/operations/regions.c b/src/lladd/operations/regions.c
index f841a6a..69b020d 100644
--- a/src/lladd/operations/regions.c
+++ b/src/lladd/operations/regions.c
@@ -12,6 +12,10 @@ typedef struct regionAllocLogArg{
 static pthread_mutex_t region_mutex = PTHREAD_MUTEX_INITIALIZER;
 pthread_t holding_mutex;
 static void TregionAllocHelper(int xid, unsigned int pageid, unsigned int pageCount, int allocationManager);
+static void TallocBoundaryTag(int xid, unsigned int page, boundary_tag* tag);
+static void TreadBoundaryTag(int xid, unsigned int page, boundary_tag* tag); 
+static void TsetBoundaryTag(int xid, unsigned int page, boundary_tag* tag); 
+static void TdeallocBoundaryTag(int xid, unsigned int page);
 
 /** This doesn't need a latch since it is only initiated within nested
     top actions (and is local to this file.  During abort(), the nested 
@@ -40,12 +44,39 @@ static int operate_alloc_region(int xid, Page * p, lsn_t lsn, recordid rid, cons
   return 0;
 }
 
-static int operate_dealloc_region(int xid, Page * p, lsn_t lsn, recordid rid, const void * datP) { 
+static int operate_dealloc_region_unlocked(int xid, Page * p, lsn_t lsn, recordid rid, const void * datP) { 
   regionAllocArg *dat = (regionAllocArg*)datP;
-  TregionDealloc(xid, dat->startPage+1);
+  
+  unsigned int firstPage = dat->startPage + 1;
+
+  boundary_tag t; 
+
+  TreadBoundaryTag(xid, firstPage - 1, &t);
+
+  t.status = REGION_VACANT;
+  t.region_xid = xid;
+  
+  TsetBoundaryTag(xid, firstPage -1, &t);
+
+  //  TregionDealloc(xid, dat->startPage+1);
   return 0;
 }
 
+static int operate_dealloc_region(int xid, Page * p, lsn_t lsn, recordid rid, const void * datP) { 
+  int ret;
+
+  pthread_mutex_lock(&region_mutex);
+  assert(0 == holding_mutex);
+  holding_mutex = pthread_self();
+
+  operate_dealloc_region_unlocked(xid, p, lsn, rid, datP);
+
+  holding_mutex = 0;
+  pthread_mutex_unlock(&region_mutex);
+
+  return ret;
+}
+
 static void TallocBoundaryTag(int xid, unsigned int page, boundary_tag* tag) {
   //printf("Alloc boundary tag at %d = { %d, %d, %d }\n", page, tag->size, tag->prev_size, tag->status);
   assert(holding_mutex == pthread_self());
@@ -84,7 +115,6 @@ static void TdeallocBoundaryTag(int xid, unsigned int page) {
   TreadBoundaryTag(xid, page, &t);
   t.status = REGION_CONDEMNED;
   t.region_xid = xid;
-  //printf("(dealloc) ");
   TsetBoundaryTag(xid, page, &t);
 
 }
@@ -331,28 +361,28 @@ void TregionDealloc(int xid, unsigned int firstPage) {
 
   regionAllocArg arg = { firstPage-1, t.size, t.allocation_manager };
 
+  assert(t.status != REGION_VACANT); 
+
   void * handle = TbeginNestedTopAction(xid, OPERATION_DEALLOC_REGION, (const byte*)&arg, sizeof(regionAllocArg));
 
-  TreadBoundaryTag(xid, firstPage - 1, &t);
+  operate_dealloc_region_unlocked(xid, 0, 0, NULLRID, (const byte*)&arg);
 
-  assert(t.status != REGION_VACANT);
-
-  t.status = REGION_VACANT;
+  /*t.status = REGION_VACANT;
   t.region_xid = xid;
 
-  TsetBoundaryTag(xid, firstPage -1, &t);
+  TsetBoundaryTag(xid, firstPage -1, &t); */
 
   firstPage --;
-  //  consolidateRegions(xid, &firstPage, &t);
 
   TendNestedTopAction(xid, handle);
+  
   holding_mutex = 0;
   pthread_mutex_unlock(&region_mutex);
 }
 
 unsigned int TregionAlloc(int xid, unsigned int pageCount, int allocationManager) { 
   // Initial implementation.  Naive first fit.
-  
+
   pthread_mutex_lock(&region_mutex);
   assert(0 == holding_mutex);
   holding_mutex = pthread_self();
diff --git a/test/lladd/check_regions.c b/test/lladd/check_regions.c
index eeb955e..51154ec 100644
--- a/test/lladd/check_regions.c
+++ b/test/lladd/check_regions.c
@@ -311,6 +311,44 @@ START_TEST(regions_lockRandomizedTest) {
   Tdeinit();
 } END_TEST
 
+START_TEST(regions_recoveryTest) { 
+
+  Tinit();
+
+  unsigned int pages[50];
+  int xid1 = Tbegin();
+  int xid2 = Tbegin();
+  for(int i = 0; i < 50; i+=2) { 
+    pages[i] = TregionAlloc(xid1, myrandom(4)+1, 1);
+    pages[i+1] = TregionAlloc(xid2, myrandom(2)+1, 1);
+  }
+  
+  fsckRegions(xid1);
+
+  Tcommit(xid1);
+
+  Tdeinit();
+
+  Tinit();
+  
+  int xid = Tbegin();
+  fsckRegions(xid);
+  
+  for(int i = 0; i < 50; i+=2) { 
+    TregionDealloc(xid, pages[i]);
+  }
+
+  fsckRegions(xid);
+  Tabort(xid);
+  fsckRegions(Tbegin());
+  Tdeinit();
+
+  Tinit();
+  fsckRegions(Tbegin());
+  Tdeinit();
+
+} END_TEST
+
 /** 
   Add suite declarations here
 */
@@ -325,6 +363,7 @@ Suite * check_suite(void) {
   tcase_add_test(tc, regions_randomizedTest);
   tcase_add_test(tc, regions_lockSmokeTest);
   tcase_add_test(tc, regions_lockRandomizedTest);
+  tcase_add_test(tc, regions_recoveryTest);
   /* --------------------------------------------- */
   tcase_add_checked_fixture(tc, setup, teardown);
   suite_add_tcase(s, tc);